* {
    /* 初始化 */
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    height: 100vh;
    /*弹性布局 居中显示*/
    display: flex;
    justify-content: center;
    align-items: center;
    /*渐变背景*/
    background: linear-gradient(to top left, #ffe29f, #ffa99f, #ff719a);
    /*溢出隐藏*/
    overflow: hidden;
    font-family: Arial, sans-serif;
}

.art-text {
    font-family: 'Pacifico', cursive;
    font-size: 1.5em;
    color: #fff;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.error-message {
    color: #ff3333;
    margin-bottom: 15px;
    padding: 10px;
    background-color: rgba(255, 255, 255, 0.3);
    border-radius: 5px;
    display: none;
}

.container {
    text-align: center;
    color: #fff;
    background-color: rgba(0, 0, 0, 0.3);
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.2);
    z-index: 2;
    position: relative;
}

.container h2 {
    font-size: 2em;
    font-weight: 300;
    letter-spacing: 2px;
    margin-bottom: 30px;
}

.form {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
}

.form input {
    outline: none;
    border: 1px solid rgba(255, 255, 255, 0.4);
    background-color: rgba(255, 255, 255, 0.2);
    width: 250px;
    padding: 12px 15px;
    border-radius: 5px;
    text-align: center;
    color: #fff;
    font-size: 16px;
    transition: all 0.3s ease;
}

.form input::placeholder {
    color: rgba(255, 255, 255, 0.7);
    font-size: 14px;
}

.form input:hover {
    background-color: rgba(255, 255, 255, 0.3);
}

.form input:focus {
    background-color: rgba(255, 255, 255, 0.4);
    width: 280px;
}

.form-actions {
    display: flex;
    gap: 10px;
    margin-top: 10px;
}

.btn-login {
    outline: none;
    background-color: #fff;
    color: #ff719a;
    border: none;
    width: 120px;
    padding: 12px;
    border-radius: 5px;
    font-size: 16px;
    cursor: pointer;
    transition: all 0.3s ease;
    text-align: center;
    text-decoration: none;
}

.btn-login:hover {
    background-color: #f5f7f9;
    transform: translateY(-2px);
}

/*背景方块*/
.bg-squares {
    list-style: none;
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
    margin: 0;
    padding: 0;
}

.bg-squares li {
    width: 40px;
    height: 40px;
    background-color: rgba(255, 255, 255, 0.15);
    position: absolute;
    bottom: -160px;
    animation: square 20s linear infinite;
    opacity: 0;
}

/* 方块动画定义 */
@keyframes square {
    0% {
        transform: translateY(0) rotate(0deg);
        opacity: 1;
    }
    100% {
        transform: translateY(-100vh) rotate(600deg);
        opacity: 0;
    }
}

/* 为每一个方块设置不同的位置、大小、动画延迟时间 */
.bg-squares li:nth-child(1) {
    left: 10%;
    animation-delay: 0s;
    animation-duration: 15s;
}

.bg-squares li:nth-child(2) {
    left: 20%;
    width: 80px;
    height: 80px;
    animation-delay: 2s;
    animation-duration: 17s;
}

.bg-squares li:nth-child(3) {
    left: 25%;
    animation-delay: 4s;
    animation-duration: 20s;
}

.bg-squares li:nth-child(4) {
    left: 40%;
    width: 60px;
    height: 60px;
    background-color: rgba(255, 255, 255, 0.25);
    animation-delay: 6s;
    animation-duration: 22s;
}

.bg-squares li:nth-child(5) {
    left: 70%;
    animation-delay: 8s;
    animation-duration: 18s;
}

.bg-squares li:nth-child(6) {
    left: 80%;
    width: 120px;
    height: 120px;
    background-color: rgba(255, 255, 255, 0.2);
    animation-delay: 3s;
    animation-duration: 25s;
}

.bg-squares li:nth-child(7) {
    left: 32%;
    width: 160px;
    height: 160px;
    animation-delay: 7s;
    animation-duration: 30s;
}

.bg-squares li:nth-child(8) {
    left: 55%;
    width: 20px;
    height: 20px;
    animation-delay: 15s;
    animation-duration: 40s;
}

.bg-squares li:nth-child(9) {
    left: 25%;
    width: 10px;
    height: 10px;
    background-color: rgba(255, 255, 255, 0.3);
    animation-delay: 2s;
    animation-duration: 40s;
}

.bg-squares li:nth-child(10) {
    left: 90%;
    width: 160px;
    height: 160px;
    animation-delay: 11s;
    animation-duration: 35s;
}